Select all that apply. Which statements describe a question that requires do-support?
A question about whether the guests arrived✓Correct answer
A question about whether the guests are inside
A question about whether the engine starts easily✓Correct answer
A question about whether the engine can restart
Explanation
A simple-tense lexical verb has no auxiliary available to invert, so do-support must be supplied. Copular be and a modal already function as auxiliaries and form questions through inversion instead.